Magnetic flap level gauge selection guide

　　The magnetic flap level gauge is a continuous level measuring instrument widely used in industrial production. This is inseparable from its simple structure, easy installation, intuitive display, long visual distance, and is very suitable for measuring the level of liquid media in containers such as tanks and storage tanks. However, due to the wide applicability of the magnetic flap level gauge and the great differences in various working conditions, this puts forward higher requirements for the purchase of the magnetic flap level gauge. This article introduces the issue of how to purchase the magnetic flap level gauge, hoping to help the magnetic flap level gauge work more reliably under various complex working conditions.

　　Generally speaking, the following points should be noted when purchasing a magnetic flap level gauge:

　　1. Have a basic understanding of the medium measured by the magnetic flap level meter

　　Instrument users should have some understanding of the working principle and basic structure of the magnetic flap level gauge, and confirm whether the viscosity of the measured medium is suitable for measurement using a magnetic flap level gauge.

　　1. The viscosity of the medium is usually less than 0.4Pa.s, and the density of the medium is generally between 0.5 and 2.0g/cm3. If the density of the medium is too low, the processing difficulty of the magnetic float will increase.

　　2. If the density is too high and the liquid is thicker, the fluidity will deteriorate, the resistance of the float moving up and down in the measuring tube body will increase, the float will be more likely to get stuck, and measurement will be impossible.

　　3. Check whether the vibration frequency of the environment is less than 25Hz and the amplitude is less than 0.5mm. Otherwise, the magnetic flap level gauge cannot work properly.

　　In short, when purchasing and selecting a magnetic flap level gauge, you should first determine whether the magnetic flap level gauge meets the measurement requirements of the actual working conditions, so as to determine whether to purchase a magnetic flap level gauge and what type of magnetic flap level gauge to buy.

　　2. Determine the installation method of the magnetic flap level gauge

　　When selecting the model, you should first determine whether to use side-to-side installation, top installation, side-top installation or top-bottom installation. Once the installation method is determined, the basic structural form of the magnetic flap level gauge is also determined.

　　3. Determine the center distance of the process flange, that is, the measuring range of the magnetic flap level gauge

　　For measuring ranges greater than 4m, considering the transportation problem, it is generally manufactured in sections; at the same time, it is necessary to add support flanges, and the user needs to provide the support flange position parameters to the manufacturer. At the same time, the nominal size, pressure level, sealing surface form and other flange parameters of the process flange are further determined.

　　4. Determine process pressure and process temperature

　　The magnitude of the process pressure determines the specifications and wall thickness of the measuring tube and the manufacturing requirements of the magnetic float (the float's pressure resistance should be one level greater than the process pressure); the process temperature determines whether the magnetic unit of the magnetic float uses a high-temperature or normal-temperature magnet, and also determines whether to choose an aluminum alloy or plastic display panel, an aluminum alloy or plastic flap, etc.; and the on-site environment determines the protection level of the display panel and other requirements.

　　5. Determine the type of medium being measured and whether it is corrosive

　　If the measured medium is a weakly corrosive medium, a 304 or 316L stainless steel magnetic flap level gauge is generally used. If the measured medium is weak acid and weak alkali wastewater discharged in industrial production, a plastic magnetic flap level gauge can also be used for measurement. If the measured medium is a strong acid or strong alkali, the pressure is less than 1.6MPa and the temperature is less than 120℃, a PTFE-lined anti-corrosion magnetic flap level gauge is generally used.

　　6. Selection when the measured medium temperature is high or low and the viscosity is high

　　When the measured medium has a high viscosity or is at a low temperature and is prone to crystallization, a steam or hot water jacketed magnetic flap level gauge can be selected; when the measured medium has a high temperature or is below zero and requires frost prevention, a vacuum jacketed thermal insulation magnetic flap level gauge can be selected.

　　7. Selection of magnetic flap level gauge when long-distance monitoring and recording are required

　　If the liquid level signal needs to be transmitted to the control center for remote monitoring and remote recording, a magnetic flap level gauge or magnetic switch with a remote transmitter can be selected, that is, a remote magnetic flap level gauge. The remote transmitter and magnetic switch are available in explosion-proof and non-explosion-proof types according to the on-site working conditions.

　　In short, when users purchase magnetic flap level gauges, they need to determine and select the magnetic flap level gauge based on the installation method, medium name, medium corrosiveness, medium density, process pressure, process temperature, process flange connection type, flange center distance and protection level and other parameters mentioned above, as well as whether there are remote transmission and explosion-proof requirements.